Portable electronics devices such as cell phones become indispensable part of daily life. As more features such as music and video added to cell phones, power consumption increases significantly. Battery life becomes a bottleneck. Furthermore, dead batteries in cell phones cause inconvenience and have safety concerns in an emergency situation. Commercially available portable charging devices such as external batteries and stand-alone solar panel are bulky and cumbersome; therefore they have not been adopted widely by consumers. Thus, there is a need in the art for methods and apparatus for fabricating an integrated kinetic energy based generator for electricity generation for portable electronic devices.